Dear all, We are pleased to announce the publication of a new paper,
Kaschner K, Quick NJ, Jewell R, Williams R, Harris CM (2012) Global Coverage of Cetacean Line-Transect Surveys: Status Quo, Data Gaps and Future Challenges. PLoS ONE 7(9): e44075. doi:10.1371/journal.pone.0044075 The pdf and data layers are available from http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044075 Abstract Knowledge of abundance, trends and distribution of cetacean populations is needed to inform marine conservation efforts, ecosystem models and spatial planning. We compiled a geo-spatial database of published data on cetacean abundance from dedicated visual line-transect surveys and encoded >1100 abundance estimates for 47 species from 430 surveys conducted worldwide from 1975-2005. Our subsequent analyses revealed large spatial, temporal and taxonomic variability and gaps in survey coverage. With the exception of Antarctic waters, survey coverage was biased toward the northern hemisphere, especially US and northern European waters. Overall, <25% of the world's ocean surface was surveyed and only 6% had been covered frequently enough (≥5 times) to allow trend estimation. Almost half the global survey effort, defined as total area (km2) covered by all survey study areas across time, was concentrated in the Eastern Tropical Pacific (ETP). Neither the number of surveys conducted nor the survey effort had increased in recent years. Across species, an average of 10% of a species' predicted range had been covered by at least one survey, but there was considerable variation among species. With the exception of three delphinid species, <1% of all species' ranges had been covered frequently enough for trend analysis. Sperm whales emerged from our analyses as a relatively data-rich species. This is a notoriously difficult species to survey visually, and we use this as an example to illustrate the challenges of using available data from line-transect surveys for the detection of trends or for spatial planning. We propose field and analytical methods to fill in data gaps to improve cetacean conservation efforts. Kind Regards Nicola Dr Nicola Quick Senior Research Scientist Scottish Oceans Institute SMRU Ltd New Technology Centre North Haugh St Andrews Fife KY16 9SR Scotland email: [email protected]<mailto:[email protected]> http://biology.st-andrews.ac.uk/staffProfile.aspx?sunID=njq Tel: +44 (0)1334 479100 Fax: +44 (0)1334 477878 www.smru.co.uk http://soi.st-andrews.ac.uk/ P Please consider whether you really need a hard copy of this email before printing it - thank you. NOTICE OF CONFIDENTIALITY: This message, and any attachments, are intended solely for the addressee and may contain privileged or confidential information. If you are not the intended recipient, any disclosure, copying, distribution or action taken or omitted to be taken in reliance on it, is prohibited and may be unlawful. If you believe that you have received this email in error, please contact the sender immediately and destroy this email. Although we have taken steps to ensure that this email and any attachments are free from any virus, we advise that, in keeping with good computing practice, the recipient should ensure they are actually virus free. SMRU LIMITED is a limited company registered in Scotland, Registered Number: 296937. Registered Office: 5 Atholl Crescent, Edinburgh EH3 8EJ.
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